Sheet metal truss structure



12,1933; E. J. w. RAGSDALE 1,939,598

SHEET METAL TRUSS STRUCTURE 2 Sheets-Sheet 1 Filed Feb. 15, 1930 I INVENTOR. EARL l-WRmsDAL-E. BY W ATTORNEY.

E. .1. w. RAGSDALE SHEET METAL TRUSS STRUCTURE Filed Feb. 15, 1950 2 Sheets-Sheet 2 v I N V EN TOR. :EARL I RAGs ALE- BYW W Y ATTORNEY.

Patented n... 12, 1933 9 1,939,598

SHEET METAL TBUSS STRUCTURE "Earl J. W. Ragsdale, Norristown, Pa., assignor to Edward G. Budd Manufacturing Company, rghlilliadelphia, Pa., a corporation of Pennsylv a Application February 15, 1930. Serial No. 428,591

9 Claims. (Cl. 189-137) The invention relates to truss structures and Figs. 9 to 17 inclusive, are views showing a particularly to hollow open truss structures modified form of the invention. adapted for aircraftconstruction. Fig. 9 represents in a perspective view a length It is a main object of my invention to provide a, of the modified truss structure.

l. truss structure of the class described in which the Figs. 10 and 11 represent respectively, short parts are readily formed out of flat sheet metal l ng hs of th outer and inner chord members. stock, and readily assembled by that easiest meth- Figs. 12 and 13 represent two forms of web od or joining sheet metal namely, spot welding, members used in this modified construction. and .which, when so assembled, a truss structure Fig. 14 represe a length of a tie p.

10 results which combines the characteristics of Figs. 15, 16 and 17 are end views representing lightness, strength and adaptability to a very three stages of the assembly. high degree. According to the form of the invention shown I attain these objects generally by the use of in Figs. 1 t0 8, the inve is shown as plight gauge sheet metal stock, preferably of rustplied to a Co um s u t having four q y 15 less alloy steel, and by building up the hollow spaced chords 10 each built up of an outer memtruss structure of longitudinal or chord members ber 11 and an inner member 12, and a plurality comprising inner hollow members opening outof web members 13 joining the adjacent chords, wardly and outer hollow members opening inthe web members according to this form of the wardly and formed in their margins for read invention all extending in the same general direc- 20 securement by spot welding or otherwise, and by tion, producing, whenconsidering the truss strucjoining adjacent chord members by web ture as a whole, the efiect of a plurality of sets bers preferably of hollow section, such as angle of CO ti uOlls ea y arranged W section, and having their ends formed to seat Each hollow (311013111 10 Comprises an d y against and to be rigidly secured to the inner facing outer hollow section member 11 of angle 25 chord members, as by spot welding prior to the s n an utw yinner ll w assembly of the outer chord members, Addisection member 12, thelatter being formed with tional strength is attained by providing longitulateral e e fla through which the Outer dinally spaced members, such as integral diaand inner members y be j as y p phram stampings extending between the i r welding. The chords may be additionally rein- 30 chord members and formed to be secured thereto forced y inwardly heading the side Wa thereas by spot welding. These also, are formed prefas shown at 5- The chord members 11 and erably of hollow section to give increased 12 y be readilyformed y rolling them om strength. flat strip stock. a Other and further objects and advantages are The Web members 13 are also of hollow section,

35 attained, as will appear from the following d such as the angle section shown, and when artailed description when read in connection with ranged as sh wn .in the preferred embodiment the attached drawings, showing several embodimay all be made identical. When in assembled m t of th i ti relation the open side of the angles present out- In the drawi wardly. One arm, as 16, of the angle section is 40 Fig. 1 shows in perspective a preferred emb dh extended at the ends thereof in the plane of the ment of my invention in a form well adapted for y of t a d widened u a 7 and 18,

use as a girder, column, beam or the like. to m' Wide Overlapping p s rough Fig. 2 shows a similar view of a, short secti which the web member is secured to the adjacent of the outer chord members, chords. The other arm 19 of the web member 45 Fi 3 ho imilar i of a, short secti terminates at each end short of the extremities 01' the inner chord member,- of the other arm and is bent upwardly at 20 and Fig. 4 is a perspective view of a web member downwardly at 21 to form Securing tabs tting according to this form of my inventi n, against and secured to the adjacent chords.

Figs. 5 and 6 show respectively edge and plan. The tabs 20 and 21 are preferably wider than the 50 view of a diaphragm member according, to the Width of the body of the arm 19 0 provide-wide form of the invention. seating surfaces through which it may be se- Fig. 7 shows, in end view, the partially assemcured to the chords, and also to space the body bled truss structure. of the web member inwardly of the edge flanges Fig. 8 is a similar view of the completely as- 14 of members 11 for a purpose which will pressembled chord and web structure. ently appear.

The extremities 20, 17 and 21, 18 form angle members which in the assembly of the web members 13 to the adjacent chords nest with the side walls, as 22 and 23 of the inner chord members 12. When so nested, the parts may be readily secured together as by spot welding.

In practice, in the assembly ,of the truss structure, I may weld all the web members overlapping one side wall of a chord member at the same time, without removing the welding tool, such as a pinch welder away from the work, this being permitted by reason of the fact that the bodies of the web members are spaced from the edge flanges 14, thus permitting the welding tool to be moved through such space from one end of the chord member to the other. This greatly expedites the operation of welding the web members to the chords.

If desired, the chord members 11 may be held properly spaced, and interbraced by longitudinally spaced diaphragms, as 24, made out of a single stamping having a central portion of annular form at 25 and corner extensions 26 extending out to the chords and provided with angle seats 2'7 embracing the two side walls 22, 23 of a chord member. These angular seats are laterally flanged, at 28, to form securing tabs through which they are spot welded to the chord members 12. The diaphragms 24 are formed with edge flanges 29 around their outer periphery and with an edge flange 30 around the central opening therein, whereby they are of intercommunicating hollow channel construction which strengthens and reinforces them.

Both the web members 13 and the transverse diaphragms 24 are secured to the inner chord members 12 before the chords 10 are closed by applying the outer chord members 11 to the inner members. Fig. '7 shows the web members applied to the inner chord members and Fig. 8 shows the complete assemblage, with the outer chord members applied to and spot welded to the flanges 14 of the inner members. This final assembling step is also greatly accelerated by reason of the fact that the bodies of the web members 13, as clearly appears in Fig. 8, are spaced from the flanges 14, thereby permitting the welding tool to be slid along the flange to be joined from one end of the structure to the other, without removing the tool from the work.

Another modification of my improved truss structure is shown in Figs. 9 to 17 inclusive. The outer and inner chord members 11, 12', in that construction are essentially the same as in the preferred form, and the web members 13, 13 of similar cross sectional form to members 13. In this construction, however, I have shown the web members 13, 13" joining adjacent chord members arranged in zig-zag fashion similar to the Warren type trussing, and I have joined the ends of the web members 13 to a side wall 22' or 23' and its adjacent edge flange 14 rather than to the two side walls of the angle section chord member 12, as in the previous construction.

Web members 13, 13" are alternately rights and lefts, as can readily be seen by a comparison of l .lgS. 12 and 13, the member 13 shown in Fig. 13 corresponding to members 13' on Fig.

9 inclined in one direction, and the member .13" in Fig. 12 being represented in Fig. 9 by the members 13" inclined in the opposite direction. The one arm, as 25, of members 13' and 13" is straight throughout and formed at its ends with elongated portions adapted to overlap the edge flanges 14 of adjacent chord members and be secured thereto, and the other arm, as 26, is

formed at the ends with oppositely bent away tabs 27 and 28 which are widened out laterally and overlap the adjacent side walls of the outwardly presenting angular chord members 12' and are secured thereto.

In the assembly of this modified form, an opposed pair of trusses may first be assembled, as shown in Fig. 15, and then the web members of the other sides may be assembled to form the hollow structure shown in Fig. 16. After this the outer chord members 11' are assembled by spot welding them to the edge flanges 14 of the inner chord members, and the entire truss structure may be additionally tied together transversely by the longitudinally spaced ribbed bands 30 encircling the outside of the structure and spot welded to the chords through the double thickness of metal where the outer and inner chord members are joined.

If desired, the same diaphragm construction could be used with this form of the invention as in the proceeding form, and the metal ribbed bands 30 might be omitted, or both methods of transverse reinforcement might be employed in either form.

In a truss structure constructed, as hereinbefore described, the characteristics of adaptability for various uses, shapes and length, of strength and of lightness are all present in a very high degree, and such a structure, while capable of general application, is particularly adapted for use in aircraft construction, where a high strength-weight ratio is very important.

While I have herein described specific embodiments of my invention, it will be understood that changes and modifications may be made by those skilled in the art which come within the spirit and scope of the invention, and I intend to cover all such by the following claims.

What I claim is:

1. A hollow sheet metal truss structure comprising hollow chord members built up of inner outwardly facing hollow members and outer members secured to the edges of the inner members, and web members of hollow section having their end portions formed to overlap the inner hollow chord members in at least two intersecting planes and separately secured thereto in said overlap.

2. A hollow sheet metal truss structure comprising chord members of outwardly facing hollow section having edge flanges, and web members connecting adjacent chord members, said web members being of hollow section and formed with end portions adapted to overlap two adjacent walls of said chord members and separately secured thereto.

3. A hollow sheet metal truss structure comprising chord members of outwardly facing hollow section having arms with edge flanges, and hollow section web members having their ends formed to overlap adjacent arms and flanges of adjacent chord members and separately secured thereto.

4. A hollow sheet metal truss structure comprising chord members of outwardly facing hollow section and hollow section web members joining adjacent chord members having their ends formed to provide a substantial overlap with two adjacent inner walls of the outwardly facing chord members and separately secured thereto.

5. A hollow sheet metal truss structure comprising chord members of outwardly facing hollow section, hollow web members joining adjacent chord members through end portions overlapping and secured to two walls of said chord members,

and longitudinally spaced transverse diaphragm 6. A sheet metal truss structure comprising hollow angle section chord members presenting outwardly, and web members joining adjacent chord members and extending in the same general dijo rection around the structure, the ends of said web members being nested with the angles of the chord members and secured thereto.

'7. A sheet metaltruss structure comprising hollow chords built up out of inner hollow section members flanged at their edges, and outer members secured to said flanged edges of the inner members, and webbing interconnecting adjacent chord members, comprising hollow section members extending between adjacent chords and having their ends formed to overlap and be separately secured to at least two adjacent walls of the inner members of the chords, all of said parts being secured together by spot welding.

8. A hollow sheet metal truss structure comprising hollow chord members of outwardly facing angular section, and web members of hollow angular section having their angularly related walls extended and widened at the ends into overlapping engagement with corresponding angularly related walls of the chord members and separately secured thereto through said widened extensions.

9. A truss structure having four chords spaced in quadrature each comprising outwardly facing, hollow angular section members, and web members of similar hollow angular section connecting pairs of adjacent chord members, said web members arranged with one wall substantially in a common plane with one wall each of a pair of adjacent chord members and extended and widened into overlapping engagement therewith and secured thereto through said widened extension, and the other wall extending at an angle to the other walls of said pair of chord members and bent and widened at their ends into overlapping engagement with said other walls of the chord members and secured thereto through said widened portions.

EARL J. W. RAGSDALE. 

